Grease gun



Aug. 14, 1956 E. w. scHlMPF GREASE GUN United States Patent GREASE GUN Ezra W. Schimpf, Marion, Kans.

Application January 5, 1953, Serial No. 329,544

6 Claims. (Cl. 222-327) This invention relates to grease guns of the so-called portable type commonly used in applying lubricants to various parts of an automobile such, for example, as the chassis or other parts requiring lubrication from time to time.

The primary object of the present invention is to provide a generally improved grease gun which may be readily operated, easily controlled when in use, and which is of such character that it may be conveniently loaded by the operator without his being subject to direct contact with the grease when carrying out the loading operation.

To the above and other ends, the invention contemplates a cylindrical container adapted for the reception of a cartridge-lil e package of grease or other lubricant which may be forcibly ejected under the action of a cornpression spring housed within the container and adapted to be conveniently released so as to urge its associatedV cup-like piston forwardly and into said package where sufficient pressure is exerted on the content of the cartridge to eject the same from the gun by way of a suitable delivery tube attached to the container at its forward end and equipped with suitable control means, whereby such tube may be opened and closed, as occasion may require, to control the delivery of lubricant by way of an outlet nozzle with which the delivery tube is equipped at its forward end.

Other objects and advantages of the invention will become apparent from the following description when taken in connection with the accompanying drawings, in which Fig. 1 is a central longitudinal sectional view showing a grease gun embodying this invention and illustrating the grease content thereof as having been partially consumed;

Fig. 2 is a fragmentary longitudinal sectional view of a control valve which is adapted to be moved from its closed position in Fig. 1 to its opened position, as shown,

' and by which ejection of the grease content of the cartridge may be manually controlled;

Fig. 3 is a fragmentary central longitudinal sectional view of the rear end of the gun, the cup-like piston being shown in its fully retracted position and there temporarily locked against displacement under the influence of its associated operating spring;

Fig. 4 is a fragmentary perspective view of the piston and illustrating the general shape of its associated locking lugs.

Fig. 5 is a rear view of the container as viewed from the right in Fig. 3; and

Fig. 6 is a side view of a grease cartridge adapted for use with the gun, the side wall of the cartridge being broken away to expose the grease content thereof.

The grease gun herein illustrated as embodying one formy of the present invention includes a cylindrical cartridge-container 10 having at its rear end a closure cap 1i which is provided, as shown most clearly in Fig. 5, with a pair of diametrically oppositely disposed bayonet slots 12, the function of which will hereinafter more clearly appear. The forward end of the container 10 is a screwlCc threaded as shown in Fig. 1 and is there provided with a removable control head indicated as a unit by the numeral 13.

As will be understood from an inspection of Fig. 1, the container 10 is adapted for the reception of a grease cartridge indicated generally at 14 in Fig. 6 and there shown as including a cylindrical body 15, fabricated from a suitable material such as cardboard or the like, and having at one end a displaceable closure 16 located within and relatively near the rear end of the cartridge, a marginal portion of the side wall of the cartridge being crimped or otherwise folded over the peripheral margin of the closure so as to effectively seal the cartridge at its rear end. The cartridge 14 is adapted for the reception of a suitable grease or other lubricant, such as that indicated at G, and is sealed at its forward end by a disc-like closure 17, temporarily held in place, as by a suitable binding 18, adapted to be conveniently removed or torn away, as indicated in dotted lines in Fig. 6, at the time the cartridge is introduced into the container 10 when conditioning the grease gun for use.

It will be understood, of course, that the cartridges may be supplied commercially with any desired type of grease contained therein, so that the gun may be con* veniently charged and conditioned for use with that particular type of grease which may be required for any given l purpose, as when lubricating one part or another of an automobile.

Within the container 10 there is slidably carried a cuplike piston 19. The piston 19 is closed at its forward end by an end wall 20 of substantial thickness and is there provided with a peripheral groove within which is held a suitable piston ring 21 consisting of leather or any other appropriate material, the outside diameter of the piston ring being somewhat less than the inside diameter of the container 10 and of such diameter that it is adapted to snugly t the inside diameter of the cartridge 14, as will be understood from an inspection of Fig. 1, wherein the piston is shown as having entered the rear end of the cartridge to a substantial extent and as having forwardly displaced the closure 16. Here it is to be noted that since the displaceable closure 16 snugly tits within the cartridge 14, where it normally serves to effectively retain the grease content within the cylindrical body 15, it follows that such closure when displaced and moved forwardly within said body will augment the action of the piston ring 21 in establishing an effective seal as between the piston and the inner wall of that body during such time as the piston is moved forwardly to expel the grease content of the cartridge.

in order that the piston 19 may be forcibly displaced forwardly of the container 10 so as to expel the grease content of the cartridge 14, there is provided a helical compression spring 22 which is of such diameter that it may be accommodated within the cylindrical side wall of the piston 19, the spring being adapted to seat on or abut against the piston Wall 20 which is provided with a slight recess 22 within which the forward end of the spring is so confined that it is prevented from shifting radially of the piston at its forward end. The rear end of the spring abuts against the inner face of the closure cap 11, which is slightly concave in contour so that the spring is etfectively retained against radially shifting at its rear end.

In order that the cartridge 14 may be readily introduced into the container 10, it becomes necessary of course to displace the piston 19 rearwardly against the action of the spring 22 and to the extent illustrated in Fig. 3. However, after such piston has been so displaced, it then becomes necessary to lock it in its rearmost position against the action of the spring; and tothis end, the side wall of the piston is provided with a pair of diametrieallyoppositely disposed andy rearwardly extending lgllile inger's 23 which are equipped at their oiter ends with a pair of locking lgs 24 adapted to enter the bayonet slots 12 vand to b e thereafter so rotatablyr displaced as Yto establish an ipterloeking cpnnection of the piston with the container 10 by way of the closure 11, It will be understood that once the lugs 24 haverentered the bayonet slots, they are then so exposed that the operator, by thumb and linger manipulatiompmay so rotate the piston 19 as to establish the desired loclting engagement as between lsaid piston 'and the containei closure capwll. Conversely; itwill be understood that the piston 19 may be released reyer'sely rotating the piston, whereupon the lspring 22, within which energy has, of eourse; been stored, may then so act on the piston as to 'forcibly movevit forwardly against the grease content of the cartridge 14. s A A The control headu13 which is carried on the front end of the eontainer 10 includes a closure oep 42o screw threadedly eonneeted to Athe container, Yas shown, the peripheral Skirt-like iiaiige ai cip, being, providecl with a bracket 2o, the outer end of ,whieh is 'forriied as a bearing |216', the function of vvhiehwll hereinafter more clearly appear. Formediintegr'ally 1lory otherwise suitably connected to central portion of the cap 2'5, is va post-like support 27 hereinafter more piarticiilar'ly referred to and adjacent to which ie proyided a feeder tube 2I`8, which ie disposed in an oft-center relation tothe cap 25 and proyided with a central passagefadapted to ciiiiiiuiiicaie with cartilage 1,4, s siivvii iii Fig. 1, 'and to deliver grease forwardly front that cartridge under the action of theI piston 19. The post 27 togetherfwith the feeder tube 28 serye as a support by which a delivery tube 29 is effectively held infan angular relationto the central axis of the container 10, as when the head is attached to that chainb'er. y

The feeder tube 28 is connected at its extreme forvara ena i0 the delivery tube 29 'and is there 'adapted is cciiiiiiuiiicaie vviih that tube sa that grease eiifeiiiig the delivery tube 29 frein 'the 'fee-lei iiibe 2s may be ejected ffr'iii the delivery 'tube by vvay ci ail a'ppiopi'ia'ie fdeta-c'hable nozzle 30 with which that tube is proyided at its forward eiid. Y

In order ton control thel passage 'of grease from the fee-'di tube 2s iiiio 'and tliiiighih ydelivery tube '29', there is proyided a suitable vcontrol 'means indicated genorally by the n urneral 31. Thisfcontr'l lnea'ns includes a valve 'sfeiii sz iiiably 'and s lid'ably supported vviihiii the ra'r end of the delivery tube 219, 'the extreme fear end of the valves'tern 32 being "slidably and rotatably l siipprfa within 'the wacker-bearing in'. Normally, ille valye tstern d2` 'is p'oi'ti'on'ed as 7SMovvn in Fig. l so that its vforyvard yend ovelie's the passage of the feeder 'tube 28, whereby communication between the cartridge 121 and the delivery tube 29 is severed. l'n order that the 'valve 32 inay be retracted so as to 'establish communica'- tion between the tubes l28 and 29, such stern is provided with nspiral groove 33 having 'a relatively steep pitch and into which projects a rivet-'like Stud 34 vCarried by the delivery tfllbe and projecting inwardly through the wall or that tube. Thuis, ii will be uiia'e'rsiocd that ifA nl@ yalye v:stern l32 is rotated in one direction as viewed from tlre ri in Fig. l, su'ch Istern, by reason f theI 'colacti'on between the vs'tnrl 34 and firewall 'surfaces of the groove 33, will be so' etraoted as tofest'a'blish conr'll'l'nication between the tubes 28 29. itis desired to move the stern 32 forwardly in 'order that communication as between the feeder tube 28 and the delivery tube 29 he severed, lit becomes necessary merely to rotate the va e 'stem 32 in an opposite direction.

Rotation of the valve 'stern 32 Vin either direction is facilitated through the Inediurn of a valve operating handle 35, detachabl'y connected tothe outer end of a radial arm 36 ,having a hub portion 37 connected Yto the valve stern and serving as an abutment limiting forward movement of the valve stem to a sufficient predetermined eitet to close the iiter end of the feeder' til 28, s shown in Fig. l.

Preferably, a compression spring 38 is carried by the valve stem and is so positioned as between the bracketbearing 26 and the hub portion 37 of the arm 36 as to exert suicient pressure on that hub to hold the valve stem against accidental displacement which would, in turn, establish undesirable communication between the feeder tube 28 and the delivery `tube 29.

Since the valve operating handle 35 is detachably connected to the arm 36 and may be of any suitable length, such handle niay be onyeniently employed, when the head 13 is remoyd, to force the piston 19 rearwardly into its latched position, as shown in Fig. 3, when it becomes necessary to conditioning the gun for use preparatory to the insertion of a grease cartridge.

Referring again to the nozzle 30, it is to be observed that such nozzle 's equipped with a suitable valve normally' stedcn the cuter end of the delivery mbe l29 and there held in closed position under the action of a compression spring 40, the outer end of which is con*- fined within a slight depression formed internally of the nozzle adjacent the exit -duct 41 thereof. The primary function of the valve 39 is to maintain the outer end vlof the delivery tube 29 Clo-sed when the gun is not in use so as to prevent possible seepage of grease from that tube into the nozzlenl). When the gun is placed in opera-y tion, the yalve 39, in response to pressure 'exerted thereon by the lubricant Within the delivery tube 29V, will open against theinfluence of its associated spring '40 so as to permit such lubricant to be expelled by way of the nozzle 30. s

Although the grease content ofthe cartridge `-1'4 `is` subjected 'to the action of the spring 22 at all times pursuant to the release of that spring, escape of grease from the container lll by Way of its Screw threaded 'connection with the closure cape 25 is prevented by reason vo' the fact that 'the cartridge is 'provide-d at its forward end with an outwardly 'extending 'sealing flange 442 which is adapted to ovc'rli the forward end 'of the container 'and there serve a's a gasket when the `closure cap is run down into impin'gi'ng engagement therewith as shown in Figure l.

In view of the foregoing description, it will become apparent that the grease `grin herein illustrated fas enibodying illy invention 'affords a convenient means b'y Whih lbri''laiit originally v"IoLi'ta-ined Within Van inexpensive tli's'jg'iosabl'e cartridge may be conveniently ejected from the -gun and utilized in the carrying out of yar-ions lubricating operations, such as those which are demanded in the maintenance of motor vehicles and the like.

What is claimed is:

1. A 'grease gun 'comprising a container, a displaceable piston slidably mounted within said container, la Aspi-ling acting en said piston Sfr-om the 'rear thereof and adapted -to be compressed'incident tothe movement of said piston rearwardly into locking position, rele'asable means lfor locking 'said piston in its reabln-o'st position whereby vsaid spring `is maintained under compression so that its energy may be utilized to forwardly displace the piston incident to release of said locking means, said releasable means including a closure vcap located 'at one "end Vof said container and having la pair of bayonet slots formed therein and a pair of locking lugs carried by said piston and adapted to enter said bayonet slots and there cooperate with said closure to releasably retain said 'piston in'itfs retracted position 'against the inu'en'ce of said spring, a grease receptacle in the forni of a cartridge disposed within said container and urging said piston rearwardly against the action of said spr-ing, `the contents of said cartridge being adapted to be subjected to the action of said piston under -the iilfle'nce 'of said spinga control head carried by said chamber 'and by way `ofivhi'ch the cartridge 'content lnay be ejected from said cartridge under the action of said spring, and manually operable control means by which the delivery of the grease content of said cartridge may be controlled.

2. A grease gun according to claim 1, wherein sa-id cartridge is characterized by the fact that it is provided at one end with an end wall adapted to be removed to permit the escape of the cartridge content under pressure and by the fact that its other end is closed by a Wall-like section adapted to be engaged by said piston and to be moved forwardly thereof along the inner wal-l of said cartridge under the action of said spring.

3. A grease gun according to claim l, wherein said cantrol head includes a delivery tube and a feeder tube, by way of which feeder tube communication may be established as between said delivery tube and said cartridge and through which the cartridge content is adapted to be directed into said delivery tube.

4. A grease gun comprising a container, a displaceable piston slidably mounted within said container, a spring acting on said piston from the rear thereof and adapted to be compressed incident to the movement of said piston rearwardly into locking position, releasable means for locking said piston in its rear-most posit-ion whereby said spring is maintained under compression so that its energy may be utilized to forwardly displace Ithe piston incident to release of said locking means, said releasable means including a closure cap located at one end of said container and having a pair of bayonet slots formed therein and a pair of locking lugs carried by said piston and adapted to enter said bayonet slots and there cooperate with said closure to releasably retain said piston in its retracted position against the iniuence of said spring, a grease receptacle in the form of a cartridge disposed within said container and the contents of which are adapted to be subjected to the action of said piston under the influence of said spring, a control head carried by said chamber and by way of which the cartrdige content may be ejected from said cartridge under the action of said spring, said head including a delivery tube and a feeder tube, by way of which feeder tube communication may be established as between said delivery tube and'said cartridge and through which the cartridge content is adapted to be directed into said delivery tube, manually operable control means by which the delivery of the grease content of said cartridge may be controlled, said control means including a valve stem carried within said delivery tube and there adapted to respectively establish and sever communication as between said feeder tube and said delivery tube, said valve stern being provided with a spiral groove and said delivcrytube being provided with a lug-like stud having one end located within said groove whereby rotat-ion of said stem will, in turn, effect longitudinal displacement of said .valve stem with reference to said deli-very tube, and means associated with said valve stem for facilitating rotation thereof.

5. A greasel gun according to claim 4, wherein pressure means in the form of -a compressible spring is associated with said valve stem and adapted to coact therewith to normally retain said valve stem in closed position.

6. A grease gun according to claim 4, wherein said cartridge is provided at one end with an outwardly extending se'aling flange impingingly held by and between said head and said container and there serving as a gasket.

References Cited in the file of this patent UNITED STATES PATENTS Engseth Aug. 24, 1954 

